Many electrical devices receive electrical power through power adapters that convert electrical power available to the device, such as the “mains” power that is often provided by local utility companies in the form of 110 Volt/220 Volt AC electrical power, into the voltage levels used by the particular electrical device. For example, laptop computers and other electrical device often use an external power supply that plugs into a wall socket to obtain electrical power and provides an electrical power output at a voltage and with an output electrical current limit that is suitable for the electrical device. Common output voltages for laptop computers include 12 Volts, 19 Volts, and other voltages depending on the design of the laptop computer. Such devices also have external power supplies that are able to provide output electrical current of several amperes at the specified output voltage. Such external power supplies are able to have a limited output electrical current where the maximum output electrical current produced by the external power supply is limited to a specified output electrical current limit value based upon the design of the device receiving the output power in order to, for example, protect against a component failure or short circuit in the device receiving the output power from the external power supply.
In another example, many electrical devices include a data communications connector that also allows electrical power to be provided to the device. One example of such a data interface connector is a Universal Serial Bus (USB) connector, such as a USB socket connector defined according to the Universal Serial Bus (USB) standard as defined by the USB Implementers Forum, Inc. It has become common for many electrical devices to utilize a socket connector as defined by the USB standard as an interface over which to receive electrical power for operations of components of the electrical device, to charge a battery or other power pack in the device, or for both. The USB standard specifies that socket connectors are to provide electrical power at five (5) Volts with a maximum current of up to 500 mA.
The various electrical power requirements of different electrical devices generally requires a person with many electrical devices to keep a number of power supplies with one power supply that is configured to provide electrical power with the voltage and electrical current required by each different electrical device. Although some power supplies are available that allow changing the output power voltage characteristics to accommodate different devices, such power supplies require specialized connectors to adapt the power supply output to the electrical device that is to receive the electrical power.
Power supplies will benefit from techniques that allow conventional power supply output ports to be reused as power output ports to provide output electrical power at various output voltages and with various output electrical current limits.